Selective rejection of touch contacts in an edge region of a touch surface

ABSTRACT

The selective rejection of touch contacts in an edge region of a touch sensor panel is disclosed. In addition, by providing certain exceptions to the rejection of edge contacts, the functionality of the touch sensor panel can be maximized. Contacts in edge bands around the perimeter of a touch sensor panel can be ignored. However, if a contact in the edge band moves beyond a threshold distance or speed, it can be recognized as part of a gesture. To accommodate different finger sizes, the size of the edge band can be modified based on the identification of the finger or thumb. Furthermore, if contacts in the center region of a touch sensor panel track the movement of contacts in the edge band, the contacts in the edge band can be recognized as part of a gesture.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/242,772, filed Sep. 30, 2008, which claims the benefit of U.S.Provisional Patent Application No. 61/019,220 filed on Jan. 4, 2008, thecontents of which are incorporated herein by reference in their entiretyfor all purposes.

FIELD OF THE INVENTION

This relates generally to input devices for computing systems, and moreparticularly, to the selective rejection of touch contacts in an edgeregion of a touch sensor panel.

BACKGROUND OF THE INVENTION

Many types of input devices are presently available for performingoperations in a computing system, such as buttons or keys, mice,trackballs, touch sensor panels, joysticks, touch screens and the like.Touch screens, in particular, are becoming increasingly popular becauseof their ease and versatility of operation as well as their decliningprice. Touch screens can include a touch sensor panel, which can be aclear panel with a touch-sensitive surface. The touch sensor panel canbe positioned in front of a display screen so that the touch-sensitivesurface covers the viewable area of the display screen. Touch screenscan allow a user to make selections and move a cursor by simply touchingthe display screen via a finger or stylus. In general, the touch screencan recognize the touch and position of the touch on the display screen,and the computing system can interpret the touch and thereafter performan action based on the touch event.

Touch sensor panels can be implemented as an array of pixels formed bymultiple drive lines (e.g. rows) crossing over multiple sense lines(e.g. columns), where the drive and sense lines are separated by adielectric material. An example of such a touch sensor panel isdescribed in Applicant's co-pending U.S. application Ser. No. 11/650,049entitled “Double-Sided Touch Sensitive Panel and Flex Circuit Bonding,”filed on Jan. 3, 2007, the contents of which are incorporated byreference herein.

However, fingers and palms inadvertently in close proximity with a touchsensor panel can cause unintended gestures to be recognized andprocessed. These inadvertent touches can often occur when the touchsensor panel is separate from but adjacent to other input devices beingused, such as a conventional keyboard or mechanical buttons or bars.Additionally, when the touch sensor panel itself is being used, fingerssuch as those used for stabilization of the hand (but not part of thegesture) or holding the device can accidentally touch the edges of thepanel and be detected.

SUMMARY OF THE INVENTION

This relates to the selective rejection of touch contacts (touch events)in an edge region of a touch sensor panel to minimize unintendedoperations. In addition, by providing certain exceptions to therejection of edge contacts, the functionality of the touch sensor panelcan be maximized.

In some embodiments, contacts in edge bands around the perimeter of atouch sensor panel can simply be ignored. However, there can be a numberof exceptions to edge rejection. For example, contacts in both thecenter area and the edge band can cause the contact in the edge band tobe recognized as part of a gesture in certain circumstances. In otherembodiments, if the contact in the edge band is stationary, it can beignored. However if the contact in the edge band moves beyond athreshold distance or speed, it can then be recognized as part of agesture.

Similarly, in trackpad embodiments, contacts within a bottom region ofthe trackpad can be ignored if stationary, but recognized as part of agesture if moving. To accommodate different finger sizes, the size ofone or more regions (e.g. the bottom or top region) can be modifiedbased on an identification of the finger or thumb.

If contacts in the center or main region of a touch sensor panel trackthe movement of contacts in the edge band or bottom region, the contactsin the edge band or bottom region may not be ignored, but instead berecognized as part of a gesture. In addition, contacts appearing in theedge band or bottom region during the recognition of gestures in thecenter or main regions of a touch sensor panel can be recognized as partof the gesture or as a control input to implement operations such asdrag lock or conversion of gestures. In other embodiments, two or morecontacts detected in an edge band can be interpreted as a gesture if thecontacts have a certain predetermined spacing (e.g., their centroidshave an x-direction separation of between 1-3 cm).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a illustrates an exemplary touch sensor panel implementing edgerejection according to one embodiment of this invention.

FIG. 1 b illustrates an exemplary touch sensor panel implementing anexception to edge rejection according to one embodiment of thisinvention.

FIG. 2 illustrates an exemplary trackpad implementing edge rejectionaccording to one embodiment of this invention.

FIG. 3 a illustrates an exemplary touch sensor panel implementing edgerejection and exceptions to edge rejection according to one embodimentof this invention.

FIG. 3 b illustrates an exemplary touch sensor panel implementing edgerejection exceptions based on the recognition of two contacts havingsynchronized movements according to one embodiment of this invention.

FIG. 4 illustrates an exemplary touch sensor panel implementingexceptions to edge rejection in order to provide a drag lock functionaccording to one embodiment of this invention.

FIG. 5 a illustrates an exemplary touch sensor panel implementingexceptions to edge rejection based on contacts in an edge region and amain region according to one embodiment of this invention.

FIG. 5 b illustrates an exemplary touch sensor panel implementingexceptions to edge rejection in order to allow a pinching gestureaccording to one embodiment of this invention.

FIGS. 5 c and 5 d illustrate an exemplary exception to edge rejectionand an example of edge rejection, respectively, according to embodimentsof the invention.

FIG. 6 illustrates an exemplary touch sensor panel employing edgerejection with a variable width edge band according to one embodiment ofthis invention.

FIG. 7 a illustrates an exemplary trackpad 700 having an integrated pickbutton and click regions according to embodiments of the invention.

FIG. 7 b illustrates an exemplary extension of the embodiment of FIG. 7a in which more than two click regions can be defined according toembodiments of the invention.

FIG. 8 illustrates an exemplary computing system operable with a touchsensor panel to implement edge rejection and exceptions to edgerejection according to one embodiment of this invention.

FIG. 9 a illustrates an exemplary mobile telephone that can include atouch sensor panel and computing system for implementing edge rejectionand exceptions to edge rejection according to one embodiment of thisinvention.

FIG. 9 b illustrates an exemplary digital media player that can includea touch sensor panel and computing system for implementing edgerejection and exceptions to edge rejection according to one embodimentof this invention.

FIG. 9 c illustrates an exemplary personal computer that can include atouch sensor panel and computing system for implementing edge rejectionand exceptions to edge rejection according to one embodiment of thisinvention.

FIG. 10 is a simplified diagram of an exemplary touch pad and displayaccording to one embodiment of this invention.

FIG. 11 is a perspective view of an exemplary input device according toone embodiment of this invention.

FIGS. 12A, 12B, 12C and 12D are simplified side views of an exemplaryinput device having a button touch pad according to one embodiment ofthis invention.

FIG. 13 is a simplified block diagram of an exemplary input deviceconnected to a computing device according to one embodiment of thisinvention.

FIG. 14 is a side view, in cross section, of an exemplary input deviceaccording to one embodiment of this invention.

FIG. 15 is another side view, in cross section, of the exemplary inputdevice of FIG. 12 according to one embodiment of this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following description of preferred embodiments, reference is madeto the accompanying drawings in which it is shown by way of illustrationspecific embodiments in which the invention can be practiced. It is tobe understood that other embodiments can be used and structural changescan be made without departing from the scope of the embodiments of thisinvention.

This relates to the selective rejection of touch contacts in an edgeregion of a touch sensor panel to minimize unintended operations. Inaddition, by providing certain exceptions to the rejection of edgecontacts, the functionality of the touch sensor panel can be maximized.

FIG. 1 a illustrates exemplary touch sensor panel 100 implementing edgerejection according to embodiments of the invention. Edge band 102(contact rejection region) can be created in an outer boundary of touchsensor panel 100, surrounding center area 104. If all contacts (e.g.fingers or palms) are detected in edge band 102, the contacts can beignored. In the example of FIG. 1 a, because touch images 106 and 108have centroids 110 and 112, respectively, located in edge band 102, thecontacts can be ignored.

FIG. 1 b illustrates a second scenario that can occur on exemplary touchsensor panel 100 according to embodiments of the invention. In theexample of FIG. 1 b, 1 f contact 114 is detected in center area 104along with contact 116 in edge band 102, a contact can be recognized inboth the center area and the edge band. The recognition of the edgecontact in this scenario in accordance with the aforementioned criteria(rejection or recognition criteria) can prevent intended gestures suchas pinching gestures with contacts starting in an edge band from beingignored.

However, when fingers are used to perform an operation such as pointingin center area 104, a so-called “pinky” or other finger inadvertentlyplaced in edge band 102 can be recognized, and an unintended gesture canbe performed instead of the pointing gesture. Therefore, in otherembodiments of the invention, if contacts 114 and 116 are detected atboth center area 104 and edge band 102, and if centroid 118 of edgecontact 116 does not move more than a threshold amount (e.g. 1 mm), itcan be ignored. However, if edge contact 116 moves more than thethreshold amount in any direction (even if there is no other fingerdetected in the center area), it can be recognized and become atrackable contact that can be part of a gesture. This recognition alsoallows for tracking operations to be performed within edge band 102.

FIG. 2 illustrates an exemplary touch sensor panel in the form oftrackpad 200 implementing edge rejection according to embodiments of theinvention. In the example of FIG. 2, adjacent to trackpad 200 is aconventional keyboard space bar 202 and mechanical pick button 204.Exemplary inadvertent touches illustrated in FIG. 2 can include thumb206 resting on space bar 202 but also inadvertently resting on trackpad200. The detected contact at 208 can be ignored so that clicks or otheractions are not accidentally generated. In addition, pinky 210inadvertently touching trackpad 200 can be ignored, and thumb 212resting on pick button 204 but also overhanging the bottom of thetrackpad at 214 can be ignored to avoid it being recognized as part ofan unintended pinch gesture.

FIG. 3 a illustrates another exemplary touch sensor panel 300implementing edge rejection according to embodiments of the invention.In the example of FIG. 3 a, touch sensor panel 300 can include a bottomregion 302 that can normally be reserved for performing certainnon-gesture actions. For example, finger taps in bottom region 302 canbe interpreted as a “click” or selection function. Thus, contacts inbottom region 302 can normally be ignored for all purposes except thesefunctions. Nevertheless, it can be desirable to have contacts in bottomregion 302 recognized as part of a gesture in certain circumstances.Therefore, according to some embodiments of the invention, in accordancewith rejection or recognition criteria, contacts 304 identified as afinger (i.e. a non-concentric image of touch of a certain thresholdsize) occurring within the bottom region can be ignored if centroid 306is stationary, but can be recognized as part of a gesture if thecentroid is not stationary. Identification of touch events is disclosedin U.S. Pat. No. 6,323,846 entitled “Method and Apparatus forIntegrating Manual Input,” the contents of which are incorporated hereinby reference in its entirety for all purposes. Stationary, as definedherein, is when the centroid moves less than a threshold amount from acomputed centroid center, or remains below some speed threshold. If thedifference between an instantaneous position and a low pass filter (LPF)averaged position value exceeds a certain threshold value, the centroidcan be considered in motion and no longer stationary. Using thiscriteria, contacts with slow drifting or rolling motions can be ignored,but faster drifts can cause the contact to be recognized as part of agesture.

In another embodiment of the invention, the size of bottom region 302 ortop region 316 (or any other edge region) can dynamically change basedon a determination that a contact was caused by a particular finger. Forexample, if a thumb is detected in bottom region 302, then based on theradius of the touch area, demarcation line 308 defining the bottomregion can be moved upward to increase the size of the bottom region.However, if a finger is detected in bottom region 302, demarcation line308 can be moved downward to decrease the size of the bottom region.Similar adjustments can be made for the top region 316, or any otheredge regions (e.g. left or right side regions).

As described above, contacts in bottom region 302 can be treated asnon-contacts independent from main region 310, although in someembodiments contacts in the bottom region can be detected and used inconjunction with contacts in the main area. For example, if the contactsin bottom region 302 move in a manner that is synchronous with orotherwise associated with movements in main region 310, the contacts inthe bottom region can be recognized along with the contacts in the mainregion as part of the gesture.

FIG. 3 b illustrates the recognition of two contacts having synchronizedmovements according to embodiments of the invention. In the example ofFIG. 3 b, if contacts 304 and 312 move in a substantially synchronousmanner with respect to each other, contact 304 can be recognized alongwith contact 312 as part of a gesture. Otherwise, contact 304 can beignored. Two contacts moving “synchronously,” as defined herein, caninclude centroids moving at approximately the same speed and/ordirection (either X and Y components together, or only the X or only theY components). In other embodiments, the synchronized movements of twocontacts can include touching down synchronously. Thus, even though oneof the two contacts may touch down within an edge band, if it touchesdown at substantially the same time as a contact touching down in themain region 310, the two contacts can be recognized as part of agesture.

FIG. 4 illustrates another exemplary exception to edge rejectionaccording to embodiments of the invention. In the example of FIG. 4, atlocation (1), contacts 416 and 418 caused by two fingers within mainregion 410 move to the left as part of an intended drag operation. Atlocation (2), contacts 416 and 418 have reached the leftmost edge ofmain region 410. If the drag operation is to continue, at location (3) athumb can be placed down in bottom region 402, causing contact 420 toappear, In this embodiment, instead of being ignored, the twopreexisting contacts 416 and 418 cause contact 420 to be recognized as aso-called “drag lock” feature of the gesture. With the drag lock inplace, the two fingers can be temporarily lifted off the touch sensorpanel and touched down again towards the center of main region 410 atlocation (4), where the leftward drag operation can continue. It shouldbe understood that this edge rejection exception can also be applied toother gestures in main region 410, wherein other contacts in the mainregion, optionally accompanied by movement, can cause subsequentcontacts in bottom region 402 to be recognized as part of a gesture.Alternatively, the subsequent contact in bottom region 402 can cause achange in the gesture recognized in main region 410. For example, apointing function in main region 410 can be converted to a drag functionas soon as a contact is either detected in, or removed from, bottomregion 402.

FIG. 5 a illustrates another exemplary exception to edge rejectionaccording to embodiments of the invention. In FIG. 5 a, stationary thumb524 detected in bottom region 502 plus finger 522 detected in mainregion 510 can be recognized as the start of a finger drag gesture, andcan remain so as long as the finger moves while the thumb remainsstationary.

FIG. 5 b illustrates yet another exemplary exception to edge rejectionaccording to embodiments of the invention. In FIG. 5 b, thumb 524detected in bottom region plus finger 522 detected in main region 510moving simultaneously towards each other can be recognized as the startof a pinch gesture.

FIG. 5 c illustrates another exemplary exception to edge rejectionaccording to embodiments of the invention. In FIG. 5 c, two or morecontacts 528 detected in an edge band (e.g. bottom region 502) can beinterpreted as a gesture if the contacts have a certain predeterminedspacing (e.g., the contacts have centroids with an x-directionseparation of between 1-3 cm). In this manner, for example, two fingersstarting a scroll in the bottom region 502 (and then moving upwards asindicated at 530) will immediately start the gesture instead of beingignored as edge straddles.

FIG. 5 d illustrates, however, that in certain regions, two contactsoccurring in an edge band can be ignored. In the example of FIG. 5 d,two contacts 532 in side region 526 occurring as a result of anedge-straddling palm can be ignored to avoid initiating an inadvertentscroll.

FIG. 6 illustrates an exemplary touch sensor panel 600 employing edgerejection with a variable width edge band 602 according to embodimentsof the invention. In the example of FIG. 6, the width of edge band 602can be dependent on a major radius of contact 606. A large major radius(above a certain threshold) of a contact whose centroid 610 is locatedwithin edge band 602 can cause the edge band to be larger in order tobetter ignore a thumb as opposed to a fingertip. The amount orpercentage of the major radius above the threshold can be used to scaleup edge band 602. Alternatively, the width of edge band 602 may not bedependent on the major radius, but instead can be based on theidentification of a particular finger type. In some embodiments, thevariable width edge band 602 may have a non-uniform width, and may bewider along one or more edges of the touch sensor panel and narroweralong one or more different edges of the touch sensor panel. Forexample, a bottom region 602 a of edge band 602 may have a width that isgreater than that of side regions 602 b and 602 c and top region 602 d.

FIG. 7 a illustrates an exemplary trackpad 700 having an integrated pickbutton according to embodiments of the invention. In the example of FIG.7 a, the trackpad 700 can be mechanically actuated by pushing on thetrackpad to generate a “click” input to implement a mechanical pickbutton. Trackpads with integrated pick buttons are described in FIGS.10-15 below.

In the trackpad 700 of FIG. 7 a, sufficient pressure anywhere on thesurface of the trackpad can cause the click to be generated, and thusthe click itself is not determinative of the location of the click.Therefore, according to embodiments of the invention, touch sensing onthe trackpad 700 can be used to determine how a click should beinterpreted. When a mechanical click is detected, the interpretation ofthe click and the resulting functionality initiated can depend on wherea touch was detected on the trackpad. In the example embodiment of FIG.7 a, the trackpad 700 is partitioned into a primary click region 702 andsecondary click region 704. When a touch is detected on the primaryclick region 702 along with a mechanical click from the trackpad, aleft-click action can be initiated, for example. Similarly, when a touchis detected on the secondary click region 704 along with a mechanicalclick from the trackpad, a right-click action can be initiated, forexample. The partitioning of the trackpad 700 can be implemented infirmware.

The example of FIG. 7 a shows equal-sized primary and secondary clickregions 702 and 704. However, in other embodiments, the size or area ofthe click regions may be unequal to account for intended usage patternsand avoid misinterpreted clicks. For example, because the secondaryclick region 704 may be less frequently used than the primary clickregion 702, the secondary click region may be made smaller and/orlocated in a region less likely to be clicked upon, such as the lowerright corner of the trackpad 700.

FIG. 7 b illustrates an exemplary extension of the embodiment of FIG. 7a in which more than two click regions can be defined. In the example ofFIG. 7 b, in addition to primary and secondary click regions 702 and704, a number of function key click regions 706, 708 and 710 can bedefined. A click of the trackpad 700 along with a touch in any of theseregions can initiate a corresponding action. Those skilled in the artwill understand that because the partitions are implemented in firmware,any number of regions, in any number of configurations, can also beemployed. In further embodiments, these regions can dynamically changein accordance with a particular usage of the computing device (e.g., inaccordance with the application being executed or the user interfacebeing displayed).

Embodiments of the invention described above can be implemented usingtouch sensor panels of the types described in U.S. application Ser. No.11/650,049 entitled “Double-Sided Touch Sensitive Panel and Flex CircuitBonding,” filed Jan. 3, 2007. Sense channels of the types described inU.S. application Ser. No. 11/649,998 entitled “Proximity and Multi-TouchSensor Detection and Demodulation,” filed Jan. 3, 2007 can be used todetect touch and hover events. The resulting image of touch can befurther processed to determine the location of the touch events, theidentification of finger contacts, and the identification of gestures asdescribed in U.S. application Ser. No. 11/428,522 entitled “IdentifyingContacts on a Touch Surface,” filed Jul. 3, 2006, U.S. application Ser.No. 11/756,211 entitled “Multi-touch Input Discrimination,” filed May31, 2007 and U.S. application Ser. No. 10/903,964 entitled “Gestures forTouch Sensitive Input Devices,” filed Jul. 30, 2004 All of the precedingapplications referred to in this paragraph are incorporated by referenceherein in their entirety for all purposes.

FIG. 8 illustrates exemplary computing system 800 that can include oneor more of the embodiments of the invention described above. Computingsystem 800 can include one or more panel processors 802 and peripherals804, and panel subsystem 806. Peripherals 804 can include, but are notlimited to, random access memory (RAM) or other types of memory orstorage, watchdog timers and the like. Panel subsystem 806 can include,but is not limited to, one or more sense channels 808, channel scanlogic 810 and driver logic 814. Channel scan logic 810 can access RAM812, autonomously read data from the sense channels and provide controlfor the sense channels. In addition, channel scan logic 810 can controldriver logic 814 to generate stimulation signals 816 at variousfrequencies and phases that can be selectively applied to drive lines oftouch sensor panel 824 at a voltage established by charge pump 815. Insome embodiments, panel subsystem 806, panel processor 802 andperipherals 804 can be integrated into a single application specificintegrated circuit (ASIC).

Touch sensor panel 824 can include a capacitive sensing medium having aplurality of drive lines and a plurality of sense lines, although othersensing media can also be used. Each intersection, adjacency ornear-adjacency of drive and sense lines can represent a capacitivesensing node and can be viewed as picture element (pixel) 826, which canbe particularly useful when touch sensor panel 824 is viewed ascapturing an “image” of touch. (In other words, after panel subsystem806 has determined whether a touch event has been detected at each touchsensor in the touch sensor panel, the pattern of touch sensors in themulti-touch panel at which a touch event occurred can be viewed as an“image” of touch (e.g. a pattern of fingers touching the panel).) Eachsense line of touch sensor panel 824 can drive sense channel 808 (alsoreferred to herein as an event detection and demodulation circuit) inpanel subsystem 806.

Computing system 800 can also include host processor 828 for receivingoutputs from panel processor 802 and performing actions based on theoutputs that can include, but are not limited to, moving an object suchas a cursor or pointer, scrolling or panning, adjusting controlsettings, opening a file or document, viewing a menu, making aselection, executing instructions, operating a peripheral device coupledto the host device, answering a telephone call, placing a telephonecall, terminating a telephone call, changing the volume or audiosettings, storing information related to telephone communications suchas addresses, frequently dialed numbers, received calls, missed calls,logging onto a computer or a computer network, permitting authorizedindividuals access to restricted areas of the computer or computernetwork, loading a user profile associated with a user's preferredarrangement of the computer desktop, permitting access to web content,launching a particular program, encrypting or decoding a message, and/orthe like. Host processor 828 can also perform additional functions thatmay not be related to panel processing, and can be coupled to programstorage 832 and display device 830 such as an LCD display for providinga UI to a user of the device. Display device 830 together with touchsensor panel 824, when located partially or entirely under the touchsensor panel, or partially or entirely integrated with the touch sensorpanel, can form touch screen 818.

Note that one or more of the functions described above can be performedby firmware stored in memory (e.g. one of the peripherals 804 in FIG. 8)and executed by panel processor 802, or stored in program storage 832and executed by host processor 828. The firmware can also be storedand/or transported within any computer-readable medium for use by or inconnection with an instruction execution system, apparatus, or device,such as a computer-based system, processor-containing system, or othersystem that can fetch the instructions from the instruction executionsystem, apparatus, or device and execute the instructions. In thecontext of this document, a “computer-readable storage medium” can beany storage medium that can contain or store the program for use by orin connection with the instruction execution system, apparatus, ordevice. The computer readable storage medium can include, but is notlimited to, an electronic, magnetic, optical, electromagnetic, infrared,or semiconductor system, apparatus or device, a portable computerdiskette (magnetic), a random access memory (RAM) (magnetic), aread-only memory (ROM) (magnetic), an erasable programmable read-onlymemory (EPROM) (magnetic), a portable optical disc such a CD, CD-R,CD-RW, DVD, DVD-R, or DVD-RW, or flash memory such as compact flashcards, secured digital cards, USB memory devices, memory sticks, and thelike.

The firmware can also be propagated within any transport medium for useby or in connection with an instruction execution system, apparatus, ordevice, such as a computer-based system, processor-containing system, orother system that can fetch the instructions from the instructionexecution system, apparatus, or device and execute the instructions. Inthe context of this document, a “transport medium” can be any mediumthat can communicate, propagate or transport the program for use by orin connection with the instruction execution system, apparatus, ordevice. The transport readable medium can include, but is not limitedto, an electronic, magnetic, optical, electromagnetic or infrared wiredor wireless propagation medium.

FIG. 9 a illustrates exemplary mobile telephone 936 that can includetouch sensor panel 924 and computing system 942 for implementing edgerejection and the edge rejection exceptions described above according toembodiments of the invention. FIG. 9 b illustrates exemplary digitalmedia player 940 that can include touch sensor panel 924 and computingsystem 942 for implementing edge rejection and the edge rejectionexceptions described above according to embodiments of the invention.FIG. 9 c illustrates exemplary personal computer 944 that can includetouch sensor panel (trackpad) 924 and computing system 942 forimplementing edge rejection and the edge rejection exceptions describedabove according to embodiments of the invention. The mobile telephone,media player, and personal computer of FIGS. 9 a, 9 b and 9 c canadvantageously benefit from the edge rejection and the edge rejectionexceptions described above because implementation of these features canminimize unintended operations while providing maximum functionality.

As discussed above, some embodiments of the invention are directed totrackpads with integrated pick buttons. One example of a trackpad withan integrated pick button is described below with reference to FIGS.10-15. However, it should be understood that other trackpads or inputdevices having integrated pick buttons also fall within the scope ofembodiments of the present invention.

FIG. 10 is a simplified diagram of an exemplary touch pad and displayaccording to embodiments of the invention. In the example of FIG. 10, atouch-sensitive track pad 10 can be a small (often rectangular) areathat includes a protective/cosmetic shield 12 and a plurality ofelectrodes 14 disposed underneath the protective shield 12. Electrodes14 may be located on a circuit board, for example a printed circuitboard (PCB). For ease of discussion, a portion of the protective shield12 has been removed to show the electrodes 14. Different electrodes 14or combinations thereof can represent different x, y positions. In oneconfiguration, as a finger 16 (or alternatively a stylus, not shown)approaches the electrode grid 14, the finger may form a capacitance withone or more electrodes proximate to the finger or may change existingcapacitances between one or more such electrodes. The circuitboard/sensing electronics (not shown) measures such capacitance changesand produces an input signal 18 which is sent to a host device 20 (e.g.,a computing device) having a display screen 22. The input signal 18 isused to control the movement of a cursor 24 on a display screen 22. Asshown, the input pointer moves in a similar x, y direction as thedetected x, y finger motion.

FIG. 11 is a simplified perspective view of an exemplary input deviceaccording to embodiments of the invention. The input device 30 isgenerally configured to send information or data to an electronic device(not shown) in order to perform an action on a display screen (e.g., viaa graphical user interface (GUI))—for example, moving an input pointer,making a selection, providing instructions, etc. The input device mayinteract with the electronic device through a wired (e.g.,cable/connector) or wireless connection (e.g., IR, bluetooth, etc.).

The input device 30 may be a stand alone unit or it may be integratedinto the electronic device. When in a stand alone unit, the input devicetypically has its own enclosure. When integrated with an electronicdevice, the input device typically uses the enclosure of the electronicdevice. In either case, the input device may be structurally coupled tothe enclosure as for example through screws, snaps, retainers, adhesivesand the like. In some cases, the input device may be removably coupledto the electronic device as for example through a docking station. Theelectronic device to which the input device is coupled may correspond toany consumer related electronic product. By way of example, theelectronic device may correspond to a computer such as a desktopcomputer, laptop computer or PDA, a media player such as a music player,a communication device such as a mobile phone, another input device suchas a keyboard, and the like.

As shown in FIG. 11, the input device 30 includes a frame 32 (or supportstructure) and a track pad 34. The frame 32 provides a structure forsupporting the components of the input device. The frame 32, in the formof a housing, may also enclose or contain the components of the inputdevice. The components, which include the track pad 34, may correspondto electrical, optical and/or mechanical components for operating theinput device 30.

Track pad 34 provides an intuitive interface configured to provide oneor more control functions for controlling various applicationsassociated with the electronic device to which it is attached. By way ofexample, the touch initiated control function may be used to move anobject or perform an action on the display screen or to make selectionsor issue commands associated with operating the electronic device. Inorder to implement the touch initiated control function, the track pad34 may be arranged to receive input from a finger (or object) movingacross the surface of the track pad 34 (e.g., linearly, radially,angular, etc.), from a finger holding a particular position on the trackpad 34 and/or by a finger tapping on a particular position of the trackpad 34. As should be appreciated, the touch pad 34 provides easyone-handed operation, i.e., lets a user interact with the electronicdevice with one or more fingers.

The track pad 34 may be widely varied. For example, the touch pad 34 maybe a conventional track pad based on the Cartesian coordinate system, orthe track pad 34 may be a touch pad based on a polar coordinate system.An example of a touch pad based on polar coordinates may be found inU.S. Pat. No. 7,046,230 to Zadesky et al., entitled “TOUCH PAD FORHANDHELD DEVICE”, filed Jul. 1, 2002, which is hereby incorporated byreference herein in its entirety for all purposes.

The track pad 34 may be used in a relative or absolute mode. In absolutemode, the track pad 34 reports the absolute coordinates of where it isbeing touched (for example x, y in the case of the Cartesian coordinatesystem or (r, θ) in the case of the polar coordinate system). Inrelative mode, the track pad 34 reports the direction and/or distance ofchange (for example, left/right, up/down, and the like). In most cases,the signals produced by the track pad 34 direct motion on the displayscreen in a direction similar to the direction of the finger as it ismoved across the surface of the track pad 34.

The shape of the track pad 34 may be widely varied. For example, thetrack pad 34 may be circular, oval, square, rectangular, triangular, andthe like. In general, the outer perimeter of the track pad 34 definesthe working boundary of the track pad 34. In the illustrated embodiment,the track pad is rectangular. Rectangular track pads are common onlaptop computers. Circular track pads allow a user to continuously swirla finger in a free manner, i.e., the finger can be rotated through 360degrees of rotation without stopping. Furthermore, the user can rotatehis or her finger tangentially from all sides thus giving it more rangeof finger positions. Both of these features may help when performing ascrolling function, making circular track pads advantageous for use withportable media players (e.g., iPod media players produced by Apple Inc.of Cupertino, Calif.). Furthermore, the size of the track pad 34generally corresponds to a size that allows them to be easilymanipulated by a user (e.g., the size of a finger tip or larger).

The track pad 34, which generally takes the form of a rigid planarplatform, includes a touchable outer track surface 36 for receiving afinger (or object) for manipulation of the track pad. Although not shownin FIG. 11, beneath the touchable outer track surface 36 is a sensorarrangement that is sensitive to such things as the pressure and/ormotion of a finger thereon. The sensor arrangement typically includes aplurality of sensors that are configured to activate as the finger sitson, taps on or passes over them. In the simplest case, an electricalsignal is produced each time the finger is positioned over a sensor. Thenumber of signals in a given time frame may indicate location,direction, speed, and acceleration of the finger on the track pad 34,i.e., the more signals, the more the user moved his finger. In mostcases, the signals are monitored by an electronic interface thatconverts the number, combination and frequency of the signals intolocation, direction, speed and acceleration information. Thisinformation may then be used by the electronic device to perform thedesired control function on the display screen. The sensor arrangementmay be widely varied. By way of example, the sensors may be based onresistive sensing, surface acoustic wave sensing, pressure sensing(e.g., strain gauge), infra red sensing, optical sensing, dispersivesignal technology, acoustic pulse recognition, capacitive sensing andthe like.

In the illustrated embodiment, the track pad 34 is based on capacitivesensing. As is generally well known, a capacitance-based track pad isarranged to detect changes in capacitance as the user moves an objectsuch as a finger around the track pad. In most cases, the capacitivetrack pad includes a protective shield, one or more electrode layers, acircuit board and associated electronics including an applicationspecific integrated circuit (ASIC). The protective shield is placed overthe electrodes; the electrodes are mounted on the top surface of thecircuit board; and the ASIC is mounted on the bottom surface of thecircuit board. The protective shield serves to protect the underlayersand to provide a surface for allowing a finger to slide thereon. Thesurface is generally smooth so that the finger does not stick to it whenmoved. The protective shield also provides an insulating layer betweenthe finger and the electrode layers. The electrode layer includes aplurality of spatially distinct electrodes. Any suitable number ofelectrodes may be used. In most cases, it would be desirable to increasethe number of electrodes so as to provide higher resolution, i.e., moreinformation can be used for things such as acceleration.

Capacitive sensing works according to the principals of capacitance. Asshould be appreciated, whenever two electrically conductive members comeclose to one another without actually touching, their electric fieldsinteract to form capacitance. In the configuration discussed above, thefirst electrically conductive member is one or more of the electrodesand the second electrically conductive member is, for example, thefinger of the user. Accordingly, as the finger approaches the touch pad,a tiny capacitance forms between the finger and the electrodes in closeproximity to the finger. The capacitance in each of the electrodes ismeasured by an ASIC located on the backside of the circuit board. Bydetecting changes in capacitance at each of the electrodes, the ASIC candetermine the location, direction, speed and acceleration of the fingeras it is moved across the touch pad. The ASIC can also report thisinformation in a form that can be used by the electronic device.

In accordance with one embodiment, track pad 34 is movable relative toframe 32 so as to initiate another set of signals (other than justtracking signals). By way of example, track pad 34 in the form of therigid planar platform may rotate, pivot, slide, translate, flex and/orthe like relative to frame 32. Track pad 34 may be coupled to frame 32and/or it may be movably restrained by frame 32. By way of example,track pad 34 may be coupled to frame 32 through screws, axels, pinjoints, slider joints, ball and socket joints, flexure joints, magnets,cushions and/or the like. Track pad 34 may also float within a space ofthe frame (e.g., gimbal). It should be noted that the input device 30may additionally include a combination of joints such as apivot/translating joint, pivot/flexure joint, pivot/ball and socketjoint, translating/flexure joint, and the like to increase the range ofmotion (e.g., increase the degree of freedom). When moved, touch pad 34is configured to actuate a circuit that generates one or more signals.The circuit generally includes one or more movement indicators such asswitches, sensors, encoders, and the like. An example of a gimbaledtrack pad may be found in patent application Ser. No. 10/643,256,entitled, “MOVABLE TOUCH PAD WITH ADDED FUNCTIONALITY,” filed Aug. 18,2003, which is hereby incorporated by reference herein in its entiretyfor all purposes.

In the illustrated embodiment, track pad 34 takes the form of adepressible button that performs a “picking” action. That is, a portionof the entire track pad 34 acts like a single or multiple button suchthat one or more additional button functions may be implemented bypressing on track pad 34 rather than tapping on the track pad or using aseparate button/separate zone. As shown in FIGS. 12A and 12B, accordingto one embodiment of the invention, track pad 34 is capable of movingbetween an upright (or neutral) position (FIG. 12A) and a depressed (oractivate) position (FIG. 12B) when a force from a finger 38, palm, hand,or other object is applied to the track pad 34. The force should not beso small as to allow for accidental activation of the button signal, butnot so large as to cause user discomfort by requiring undue pressure.Track pad 34 is typically biased in the upright position as for examplethrough a flexure hinge, a spring member, or magnets. Track pad 34 movesto the activate position when the bias is overcome by an object pressingon track pad 34. As shown in FIG. 12C, the track pad 34 may be pivotedat one end such that the activate position is slightly inclined withrespect to the neutral position. When the finger (or other object) isremoved from track pad 34, the biasing member urges it back towards theneutral position. A shim or other structure (not shown) may preventtrack pad 34 from overshooting the neutral position as it returns. Forexample, a portion of frame 32 may extend outwardly above a portion oftrack pad 34 so as to stop track pad 34 at the neutral position. In thisway, the track pad surface can be kept flush with frame 32 if desired.For example, in laptop computers or handheld media devices, it may bedesirable to have the track pad flush with the housing of the computeror device.

As shown in FIG. 12A, in the upright/neutral position, track pad 34generates tracking signals when an object such as a user's finger ismoved over the top surface of the touch pad in the x,y plane. AlthoughFIG. 12A depicts the neutral position as being upright, the neutralposition may be situated at any orientation. As shown in FIG. 12B, inthe depressed position (z direction), track pad 34 generates one or morebutton signals. The button signals may be used for variousfunctionalities including but not limited to making selections orissuing commands associated with operating an electronic device. By wayof example, in the case of a music player, the button functions may beassociated with opening a menu, playing a song, fast forwarding a song,seeking through a menu and the like. In the case of a laptop computer,the button functions can be associated with opening a menu, selectingtext, selecting an icon, and the like. As shown in FIG. 12D, inputdevice 30 may be arranged to provide both the tracking signals and thebutton signal at the same time, i.e., simultaneously depressing thetouch pad 34 in the z direction while moving tangentially along thetrack surface (i.e., in the x, y directions). In other cases, inputdevice 30 may be arranged to only provide a button signal when touch pad34 is depressed and a tracking signal when the touch pad 34 is upright.

To elaborate, track pad 34 is configured to actuate one or more movementindicators, which are capable of generating the button signal when trackpad 34 is moved to the activate position. The movement indicators aretypically located within frame 32 and may be coupled to track pad 34and/or frame 32. The movement indicators may be any combination ofswitches and sensors. Switches are generally configured to providepulsed or binary data such as activate (on) or deactivate (off). By wayof example, an underside portion of track pad 34 may be configured tocontact or engage (and thus activate) a switch when the user presses ontrack pad 34. The sensors, on the other hand, are generally configuredto provide continuous or analog data. By way of example, the sensor maybe configured to measure the position or the amount of tilt of touch pad34 relative to the frame when a user presses on the track pad 34. Anysuitable mechanical, electrical and/or optical switch or sensor may beused. For example, tact switches, force sensitive resistors, pressuresensors, proximity sensors and the like may be used.

Track pads 10 and 30 shown in FIGS. 10-12 may, in some embodiments, bemulti-touch trackpads. Multi-touch consists of a touch surface (screen,table, wall, etc.) or touchpad, as well as software that recognizesmultiple simultaneous touch points, as opposed to the standardtouchscreen (e.g., computer touchpad, ATM), which recognizes only onetouch point. This effect is achieved through a variety of means,including but not limited to capacitive sensing, resistive sensing,surface acoustic wave sensing, heat, finger pressure, high capture ratecameras, infrared light, optic capture, tuned electromagnetic induction,and shadow capture. An example of a multi-touch mobile phone is theiPhone produced by Apple Inc. of Cupertino, Calif. An example of amulti-touch media device is the iPod Touch produced by Apple Inc.Examples of laptop computers having multi-touch track pads are theMacBook Air and MacBook Pro produced by Apple Inc. All of the inputdevices described herein may employ multi-touch technology in someembodiments; alternatively the input devices described herein may employsingle touch track pads.

FIG. 13 is a simplified block diagram of a computing system 39, inaccordance with one embodiment of the present invention. The computingsystem generally includes an input device 40 operatively connected to acomputing device 42. By way of example, the input device 40 maygenerally correspond to the input device 30 shown in FIGS. 11 and 12,and the computing device 42 may correspond to a laptop computer, desktopcomputer, PDA, media player, mobile phone, smart phone, video game orthe like. As shown, input device 40 includes a depressible track pad 44and one or more movement indicators 46. Track pad 44 is configured togenerate tracking signals and movement indicator 46 is configured togenerate a button signal when the track pad 44 is depressed. Althoughtrack pad 44 may be widely varied, in this embodiment, track pad 44includes capacitance sensors 48 and a control system 50 for acquiringthe position signals from sensors 48 and supplying the signals tocomputing device 42. Control system 50 may include an applicationspecific integrated circuit (ASIC) that is configured to monitor thesignals from sensors 48, to compute the location (Cartesian or angular),direction, speed and acceleration of the monitored signals and to reportthis information to a processor of computing device 42. Movementindicator 46 may also be widely varied. In this embodiment, however,movement indicator 46 takes the form of a switch that generates a buttonsignal when track pad 44 is depressed. Switch 46 may correspond to amechanical, electrical or optical style switch. In one particularimplementation, switch 46 is a mechanical style switch that includes aprotruding actuator 52 that may be pushed by track pad 44 to generatethe button signal. By way of example, the switch may be a tact switch ortactile dome.

Both track pad 44 and switch 46 are operatively coupled to computingdevice 42 through a communication interface 54. The communicationinterface provides a connection point for direct or indirect connectionbetween the input device and the electronic device. Communicationinterface 54 may be wired (wires, cables, connectors) or wireless (e.g.,transmitter/receiver).

Computing device 42 generally includes a processor 55 (e.g., CPU ormicroprocessor) configured to execute instructions and to carry outoperations associated with the computing device 42. For example, usinginstructions retrieved for example from memory, the processor maycontrol the reception and manipulation of input and output data betweencomponents of the computing device 42. In most cases, processor 55executes instruction under the control of an operating system or othersoftware. Processor 55 can be a single-chip processor or can beimplemented with multiple components.

Computing device 42 also includes an input/output (I/O) controller 56that is operatively coupled to processor 54. I/O controller 56 may beintegrated with processor 54 or it may be a separate component, asshown. I/O controller 56 is generally configured to control interactionswith one or more I/O devices that can be coupled to computing device 42,for example, input device 40. I/O controller 56 generally operates byexchanging data between computing device 42 and I/O devices that desireto communicate with computing device 42.

Computing device 42 also includes a display controller 58 that isoperatively coupled to processor 54. Display controller 58 may beintegrated with processor 54 or it may be a separate component, asshown. Display controller 58 is configured to process display commandsto produce text and graphics on a display screen 60. By way of example,display screen 60 may be a monochrome display, color graphics adapter(CGA) display, enhanced graphics adapter (EGA) display,variable-graphics-array (VGA) display, super VGA display, liquid crystaldisplay (LCD) (e.g., active matrix, passive matrix and the like),cathode ray tube (CRT), plasma displays, backlit light-emitting diode(LED) LCD displays, or the like.

In one embodiment (not shown), track pad 44 can comprise a glass surfacefunctioning not only as a touch-sensitive surface, but also as a displayscreen; in this case display screen 60 shown in FIG. 13 would beintegrated with the glass surface of the track pad 44. This could beuseful in computing devices (e.g., media players or mobile phones)having touch sensitive displays. An example of a media player having atouch sensitive display is the iPod Touch produced by Apple Inc. ofCupertino Calif. An example of a mobile phone having a touch sensitivedisplay is the iPhone produced by Apple Inc. of Cupertino Calif.

In most cases, processor 54 together with an operating system operatesto execute computer code and produce and use data. The computer code anddata may reside within a program storage area 62 that is operativelycoupled to processor 54. Program storage area 62 generally provides aplace to hold data that is being used by computing device 42. By way ofexample, the program storage area may include Read-Only Memory (ROM),Random-Access Memory (RAM), hard disk drive and/or the like. Thecomputer code and data could also reside on a removable program mediumand loaded or installed onto the computing device when needed. In oneembodiment, program storage area 62 is configured to store informationfor controlling how the tracking and button signals generated by inputdevice 40 are used by computing device 42.

FIG. 14 shows one embodiment of an input device, generally shown at 70,comprising a track pad 72 connected to a frame 76. Frame 76 may be ahousing for a stand alone input device, or it may be a casing foranother device which incorporates track pad 72, for example a laptopcomputer, desktop computer, hand held media device, PDA, mobile phone,smart phone, etc. Track pad 72 includes various layers including anouter touch-sensitive track surface 74 for tracking finger movements.Track surface 74 may also provide a low friction cosmetic surface. Inone embodiment, track pad 72 is based on capacitive sensing; therefore,it includes an electrode layer 80, which, for example, may beimplemented on a PCB. In the case of capacitive sensing, track surface74 is a dielectric material. A stiffener 84 is located below electrodelayer 80. Stiffener 84 is shown in FIG. 14 and FIG. 15, but in someembodiments may be omitted. Stiffener 84 may be used to compensate forthe inherent flexibility of electrode layer 80. Electrode layer 80responds to finger movements along to track surface 74 by sendingsignals to sensor 82. In the case of capacitive sensing, electrode layer80 registers changes in capacitance based on finger movements and sensor82 is a capacitive sensor. In this way, track pad 72 incorporates atouch sensor arrangement. Sensor 82 is shown disposed on the bottom ofelectrode layer 80, but it may be located elsewhere in otherembodiments. If, as in the illustrated embodiment, sensor 82 is locatedon a movable part of track pad 72, the input device may incorporate aflexible electrical connection (not shown) capable of moving with thesystem.

A movement indicator 78 is disposed on the bottom of track pad 72.Movement indicator 78 may be widely varied, however, in this embodimentit takes the form of a mechanical switch, which is typically disposedbetween the track pad 72 and the frame 76. In other embodiments,movement indicator 78 may be a sensor, for example an electrical sensor.Movement indicator 78 may be attached to frame 76 or to track pad 72. Inthe illustrated embodiment, movement indicator 78 is attached to thebottom side of electrode layer 80. By way of example, if electrode layer80 is located on a PCB, movement indicator 78 may be located on thebottom of the PCB. In another example, movement indicator 78 may tackthe form of a tact switches and more particularly, may be an SMT domeswitches (dome switch packaged for SMT).

Track pad 72 is shown in its neutral position in FIG. 14, where movementsensor 78 is not in contact with frame 76. When a user applies adownward pressure to track surface 74, track pad 72 may move downwardcausing movement sensor 78 to register this change in position. In theillustrated embodiment, movement sensor 78 (a tact switch) would contacteither frame 76, or in this case set screw 88. Set screw 88 may bemanually adjusted to alter the distance between the neutral and activatepositions. In one embodiment (not shown), set screw 88 may directly abutmovement sensor 78 in the neutral position, such that there is no slackor pre-travel in the system. A flexure hinge 86 connects track pad 72with frame 76. Flexure hinge 86 is a resilient material that flexes whena force is applied, but exerts a restoring force so as to urge track pad72 back towards the neutral position. In one embodiment, flexure hinge86 may be thin spring steel.

As shown in FIG. 15, flexure hinge 86 will flex when a user pushes downon track surface 74. Flexure 86 also urges track pad 72 towards itsneutral position, which in the illustrated embodiment shown in FIG. 14is horizontal. In this way, a user can press down virtually anywhere ontrack surface 74 and cause a “pick,” meaning that movement indicator 78will register this depression. This is in contrast to prior track padswhich incorporate separate track zones and pick zones. Being able topick anywhere on track surface 74 will provide the user with a moreintuitive and pleasurable interface. For example, a user may be able togenerate tracking and button signals with a single finger without everhaving to remove the finger from track surface 74. In contrast, a useroperating a track pad with separate track and pick zones may, forexample, use a right hand for tracking and a left hand for picking, or aforefinger for tracking and thumb picking.

A shoulder 90, which may be an extension of frame 76 or a discretemember, blocks track pad 72 from travelling past its neutral position bycontacting a part of track pad 72, for example stiffener 84. In thisway, track surface 74 may be kept substantially flush with a top surfaceof frame 76. There may be a shock absorber or upstop (not shown)incorporated in conjunction with shoulder 90 to cushion contacts betweentrack pad 72 and shoulder 90.

As should be appreciated, the pick generated by pressing on tracksurface 74 may include selecting an item on the screen, opening a fileor document, executing instructions, starting a program, viewing a menu,and/or the like. The button functions may also include functions thatmake it easier to navigate through the electronic system, as forexample, zoom, scroll, open different menus, home the input pointer,perform keyboard related actions such as enter, delete, insert, pageup/down, and the like.

Flexure hinge 86 allows for a movable track pad in the minimum verticalspace possible. Minimum vertical space is achieved because flexure hinge86 is thin and is generally situated parallel to a bottom layer of trackpad 72; consequently, flexure hinge 86 does not appreciably add to thethickness of track pad 72. Therefore, this arrangement is feasible foruse in ultrathin laptop computers. In such ultrathin laptop computerapplications, vertical space is extremely limited. In the past, the sizeof electrical components was often the limiting feature as to how smallelectrical devices could be made. Today, electrical components areincreasingly miniaturized, meaning that mechanical components (e.g.,movable track pads) may now be the critical size-limiting components.With this understanding, it is easy to appreciate why linear-actuation(e.g., supporting a movable track pad by coil springs or the like) isnot ideal in some applications. Furthermore, using springs may addunnecessary complexity (increased part count, higher cost, higherfailure rates, etc. . . . ) to the manufacturing process. Anotherdisadvantage of springs is that in some embodiments springs may mask orcompromise the tactile switch force profile. In contrast, flexure 86 candeliver a substantially consistent feel across the track surface 74, andgive the user a more faithful representation of the tactile switch forceprofile.

Referring now to FIG. 15, according to one embodiment of the presentinvention, when a user presses on track surface 74 of track pad 72,track pad 72 pivots downwardly activates switch 78 disposed underneath.When activated, switch 78 generates button signals that may be used byan electronic device connected to input device 70. Flexure 86 canconstrain track pad 72 to move substantially about only one axis. Thiscan be accomplished by, for example, using multiple flexures arrangedalong an axis on one side of track pad 72, such as the rear side.Furthermore, if track pad 72 is made stiff (for example, by inclusion ofstiffener 84 if necessary), a leveling architecture is achieved. Inother words, flexure hinge 86 urges track pad 72 towards its neutralposition and also permits movement about substantially only one axis,i.e., the axis along which flexure hinge 86 is connected to frame 76.

Although embodiments of this invention have been fully described withreference to the accompanying drawings, it is to be noted that variouschanges and modifications will become apparent to those skilled in theart. Such changes and modifications are to be understood as beingincluded within the scope of embodiments of this invention as defined bythe appended claims.

What is claimed is:
 1. A method for selectively rejecting contacts on atouch sensor panel, comprising: designating one or more regions alongone or more edges in the touch sensor panel as contact rejectionregions; and selectively rejecting or recognizing a first contactdetected within the one or more contact rejection regions in accordancewith rejection or recognition criteria, wherein the first contact isrejected unless the first contact is simultaneously detected with one ormore second contacts detected in a main region of the touch sensorpanel, the main region being separate from the one or more contactrejection regions.
 2. The method of claim 1, further comprisingrecognizing the first contact if the one or more second contacts aredetected within the main region of the touch sensor panel and the firstcontact is detected as having movement exceeding a particular threshold.3. The method of claim 1, further comprising recognizing the firstcontact if the first contact is recognized as a part or all of aparticular gesture including the one or more second contacts.
 4. Themethod of claim 1, further comprising varying a size of the contactrejection region in accordance with an identification of a finger orthumb as a cause of the first contact.
 5. The method of claim 1, furthercomprising recognizing the first contact if the first and the one ormore second contacts have substantially synchronous movement.
 6. Themethod of claim 3, further comprising recognizing the one or more secondcontacts as part of a drag gesture and the first contact as being a draglock component of the drag gesture.
 7. The method of claim 1, furthercomprising recognizing the first contact as changing a first gesture ifthe one or more second contacts are detected as performing the firstgesture within the main region of the touch sensor panel.
 8. The methodof claim 1, further comprising varying a size of the contact rejectionregion in accordance with a computed parameter of the first contact. 9.The method of claim 1, further comprising assigning different widths tothe contact rejection regions along various edges of the touch sensorpanel.
 10. The method of claim 1, further comprising recognizing thefirst contact if at least one of the one or more second contacts isdetected within the main region of the touch sensor panel and touchesdown at substantially the same time as the first contact.
 11. Anon-transitory computer-readable storage medium storing program code forselectively rejecting contacts on a touch sensor panel, the program codefor causing performance of a method comprising: selectively rejecting orrecognizing a first contact detected in one or more designated contactrejection regions in the touch sensor panel in accordance with rejectionor recognition criteria, wherein the first contact is rejected unlessthe first contact is simultaneously detected with one or more secondcontacts detected in a main region of the touch sensor panel, the mainregion being separate from the one or more contact rejection regions,and wherein the one or more contact rejection regions are located alongone or more edges of the touch sensor panel.
 12. The non-transitorycomputer-readable storage medium of claim 11, the program code furtherfor recognizing the first contact if the one or more second contacts aredetected within the main region of the touch sensor panel and the firstcontact is detected as having movement exceeding a particular threshold.13. The non-transitory computer-readable storage medium of claim 11, theprogram code further for recognizing the first contact if the firstcontact is recognized as a part or all of a particular gesture includingthe one or more second contacts.
 14. The non-transitorycomputer-readable storage medium of claim 11, the program code furtherfor varying a size of the contact rejection region in accordance with anidentification of a finger or thumb as a cause of the first contact. 15.The non-transitory computer-readable storage medium of claim 11, theprogram code further for recognizing the first contact if the first andthe one or more second contacts have substantially synchronous movement.16. The non-transitory computer-readable storage medium of claim 13, theprogram code further for recognizing the one or more second contacts aspart of a drag gesture and the first contact as being a drag lockcomponent of the drag gesture.
 17. The non-transitory computer-readablestorage medium of claim 11, the program code further for recognizing thefirst contact as changing a first gesture if the one or more secondcontacts are detected as performing the first gesture within the mainregion of the touch sensor panel.
 18. The non-transitorycomputer-readable storage medium of claim 11, the program code furtherfor varying a size of the contact rejection region in accordance with acomputed parameter of the first contact.
 19. The non-transitorycomputer-readable storage medium of claim 11, the program code furtherfor assigning different widths to the contact rejection regions alongvarious edges of the touch sensor panel.
 20. The computer-readablestorage medium of claim 11, the program code further for recognizing thefirst contact if at least one of the one or more second contacts isdetected within the main region of the touch sensor panel and touchesdown at substantially the same time as the first contact.
 21. A mobiletelephone including computer-readable storage medium storing programcode for selectively rejecting contacts on a touch sensor panel, theprogram code for causing performance of a method comprising: selectivelyrejecting or recognizing a first contact detected in one or moredesignated contact rejection regions in the touch sensor panel inaccordance with rejection or recognition criteria, wherein the firstcontact is rejected unless the first contact is simultaneously detectedwith one or more second contacts detected in a main region of the touchsensor panel, the main region being separate from the one or morecontact rejection regions, and wherein the one or more contact rejectionregions are located along one or more edges of the touch sensor panel.22. A personal computer including computer-readable storage mediumstoring program code for selectively rejecting contacts on a touchsensor panel, the program code for causing performance of a methodcomprising: selectively rejecting or recognizing a first contactdetected in one or more designated contact rejection regions in thetouch sensor panel in accordance with rejection or recognition criteria,wherein the first contact is rejected unless the first contact issimultaneously detected with one or more second contacts detected in amain region of the touch sensor panel, the main region being separatefrom the one or more contact rejection regions, and wherein the one ormore contact rejection regions are located along one or more edges ofthe touch sensor panel.